High Percentage of Regulatory T Cells before and after Vitamin B₁₂ Treatment in Patients with Pernicious Anemia

Abstract

Introduction: In some previous studies, vitamin B₁₂ treatment showed immunomodulatory effects and restored the immunological abnormalities in patients with pernicious anemia (PA). In the present study, peripheral blood T cell subsets, including regulatory T cells (T_regs), were examined before and after vitamin B₁₂ treatment in PA patients. Patients and Methods: The percentages of CD4, CD8, Th1, Th2 and T_regs were examined in 23 PA patients before vitamin B₁₂ treatment, in 23 other PA patients after vitamin B₁₂ treatment and in 28 healthy controls. Results: The mean percentage of CD8+ T cells was significantly higher in the control group (23.0%; 95% CI, 20.4-25.6%) than in the pre- (16.0%; 95% CI, 12.1-20.0%) and posttreatment groups (15.2%; 95% CI, 11.8-18.6%; p < 0.05). The CD4/CD8 ratio was significantly lower in the control group (2.01; 95% CI, 1.66-2.34) than in the pre- (3.45; 95% CI, 2.55-7.80) and posttreatment groups (2.97; 95% CI, 2.22-3.72; p < 0.05). There was no significant difference in the mean Th1/Th2 ratio among these groups. There were significant increases in the mean percentage of T_regs in the pre- (6.29%; 95% CI, 5.04-7.54%) and posttreatment groups (7.77%; 95% CI, 6.34-9.20%) compared with the control group (4.18%; 95% CI, 3.92-4.47%; p < 0.05). Conclusions: The percentage of T_regs was significantly higher in PA patients than in normal subjects, and this high T_reg percentage was not different before and after vitamin B₁₂ treatment. Other immunological alterations also did not recover after vitamin B₁₂ treatment, so that these immunological changes appear to be the cause of PA and are not induced by vitamin B₁₂ deficiency.

Unusual association between erythema nodosum and autoimmune atrophic gastritis

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Nutritional Modulation of Immune and Central Nervous System Homeostasis: The Role of Diet in Development of Neuroinflammation and Neurological Disease

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